[The following is an exact transcript of this podcast.]
Man-made light sources can really throw animals for a loop. Moths can't tear themselves away from lightbulbs, and newly hatched sea turtles often shun moonlit ocean waves for the bright lights of inland cities. But a study in January's issue of the journal Frontiers in Ecology and the Environment says direct light sources are only part of the problem.
Light that reflects off shiny urban surfaces, like roads, parking lots and buildings, has an equally devastating power to attract. That's because such polarized light means one thing to most animals—water. For example insects like dragonflies make nocturnal flights to lay their eggs using horizontally polarized light as a beacon. That light might bring them to a stream or pond, but a well-lit interstate is equally alluring. If enough insects lay eggs on the road instead of in the water, the entire food web can be disrupted.
But there are ways to dim our influential lights, the scientists say. Bugs are less attracted to roadways with white hatch marks on the pavement. And light-colored curtains can keep birds from slamming into dark buildings. Simple fixes, really, to keep basic instincts from turning into fatal attractions.